Quelle  commands.c   Sprache: C

// SPDX-License-Identifier: LGPL-2.1+
// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
#define _GNU_SOURCE
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <limits.h>

#include <thermal.h>
#include "thermal_nl.h"

static struct nla_policy thermal_genl_policy[THERMAL_GENL_ATTR_MAX + 1] = {
 /* Thermal zone */
 [THERMAL_GENL_ATTR_TZ]                  = { .type = NLA_NESTED },
 [THERMAL_GENL_ATTR_TZ_ID]               = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_TEMP]             = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_TRIP]             = { .type = NLA_NESTED },
 [THERMAL_GENL_ATTR_TZ_TRIP_ID]          = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_TRIP_TEMP]        = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_TRIP_TYPE]        = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_TRIP_HYST]        = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_MODE]             = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_CDEV_WEIGHT]      = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_TZ_NAME]             = { .type = NLA_STRING },

 /* Governor(s) */
 [THERMAL_GENL_ATTR_TZ_GOV]              = { .type = NLA_NESTED },
 [THERMAL_GENL_ATTR_TZ_GOV_NAME]         = { .type = NLA_STRING },

 /* Cooling devices */
 [THERMAL_GENL_ATTR_CDEV]                = { .type = NLA_NESTED },
 [THERMAL_GENL_ATTR_CDEV_ID]             = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_CDEV_CUR_STATE]      = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_CDEV_MAX_STATE]      = { .type = NLA_U32 },
 [THERMAL_GENL_ATTR_CDEV_NAME]           = { .type = NLA_STRING },

        /* Thresholds */
        [THERMAL_GENL_ATTR_THRESHOLD]       = { .type = NLA_NESTED },
        [THERMAL_GENL_ATTR_THRESHOLD_TEMP]      = { .type = NLA_U32 },
        [THERMAL_GENL_ATTR_THRESHOLD_DIRECTION] = { .type = NLA_U32 },
};

static int parse_tz_get(struct genl_info *info, struct thermal_zone **tz)
{
 struct nlattr *attr;
 struct thermal_zone *__tz = NULL;
 size_t size = 0;
 int rem;

 nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_TZ], rem) {

  if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_ID) {

   size++;

   __tz = realloc(__tz, sizeof(*__tz) * (size + 2));
   if (!__tz)
    return THERMAL_ERROR;

   __tz[size - 1].id = nla_get_u32(attr);
  }


  if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_NAME)
   nla_strlcpy(__tz[size - 1].name, attr,
        THERMAL_NAME_LENGTH);
 }

 if (__tz)
  __tz[size].id = -1;

 *tz = __tz;

 return THERMAL_SUCCESS;
}

static int parse_cdev_get(struct genl_info *info, struct thermal_cdev **cdev)
{
 struct nlattr *attr;
 struct thermal_cdev *__cdev = NULL;
 size_t size = 0;
 int rem;

 nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_CDEV], rem) {

  if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_ID) {

   size++;

   __cdev = realloc(__cdev, sizeof(*__cdev) * (size + 2));
   if (!__cdev)
    return THERMAL_ERROR;

   __cdev[size - 1].id = nla_get_u32(attr);
  }

  if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_NAME) {
   nla_strlcpy(__cdev[size - 1].name, attr,
        THERMAL_NAME_LENGTH);
  }

  if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_CUR_STATE)
   __cdev[size - 1].cur_state = nla_get_u32(attr);

  if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_MAX_STATE)
   __cdev[size - 1].max_state = nla_get_u32(attr);
 }

 if (__cdev)
  __cdev[size].id = -1;

 *cdev = __cdev;

 return THERMAL_SUCCESS;
}

static int parse_tz_get_trip(struct genl_info *info, struct thermal_zone *tz)
{
 struct nlattr *attr;
 struct thermal_trip *__tt = NULL;
 size_t size = 0;
 int rem;

 nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_TZ_TRIP], rem) {

  if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_ID) {

   size++;

   __tt = realloc(__tt, sizeof(*__tt) * (size + 2));
   if (!__tt)
    return THERMAL_ERROR;

   __tt[size - 1].id = nla_get_u32(attr);
  }

  if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_TYPE)
   __tt[size - 1].type = nla_get_u32(attr);

  if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_TEMP)
   __tt[size - 1].temp = nla_get_u32(attr);

  if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_HYST)
   __tt[size - 1].hyst = nla_get_u32(attr);
 }

 if (__tt)
  __tt[size].id = -1;

 tz->trip = __tt;

 return THERMAL_SUCCESS;
}

static int parse_tz_get_temp(struct genl_info *info, struct thermal_zone *tz)
{
 int id = -1;

 if (info->attrs[THERMAL_GENL_ATTR_TZ_ID])
  id = nla_get_u32(info->attrs[THERMAL_GENL_ATTR_TZ_ID]);

 if (tz->id != id)
  return THERMAL_ERROR;

 if (info->attrs[THERMAL_GENL_ATTR_TZ_TEMP])
  tz->temp = nla_get_u32(info->attrs[THERMAL_GENL_ATTR_TZ_TEMP]);

 return THERMAL_SUCCESS;
}

static int parse_tz_get_gov(struct genl_info *info, struct thermal_zone *tz)
{
 int id = -1;

 if (info->attrs[THERMAL_GENL_ATTR_TZ_ID])
  id = nla_get_u32(info->attrs[THERMAL_GENL_ATTR_TZ_ID]);

 if (tz->id != id)
  return THERMAL_ERROR;

 if (info->attrs[THERMAL_GENL_ATTR_TZ_GOV_NAME]) {
  nla_strlcpy(tz->governor,
       info->attrs[THERMAL_GENL_ATTR_TZ_GOV_NAME],
       THERMAL_NAME_LENGTH);
 }

 return THERMAL_SUCCESS;
}

static int parse_threshold_get(struct genl_info *info, struct thermal_zone *tz)
{
 struct nlattr *attr;
 struct thermal_threshold *__tt = NULL;
 size_t size = 0;
 int rem;

 /*
 * The size contains the size of the array and we want to
 * access the last element, size - 1.
 *
 * The variable size is initialized to zero but it will be
 * then incremented by the first if() statement. The message
 * attributes are ordered, so the first if() statement will be
 * always called before the second one. If it happens that is
 * not the case, then it is a kernel bug.
 */
 nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_THRESHOLD], rem) {

  if (nla_type(attr) == THERMAL_GENL_ATTR_THRESHOLD_TEMP) {

   size++;

   __tt = realloc(__tt, sizeof(*__tt) * (size + 2));
   if (!__tt)
    return THERMAL_ERROR;

   __tt[size - 1].temperature = nla_get_u32(attr);
  }

  if (nla_type(attr) == THERMAL_GENL_ATTR_THRESHOLD_DIRECTION)
   __tt[size - 1].direction = nla_get_u32(attr);
 }

 if (__tt)
  __tt[size].temperature = INT_MAX;

 tz->thresholds = __tt;

 return THERMAL_SUCCESS;
}

static int handle_netlink(struct nl_cache_ops *unused,
     struct genl_cmd *cmd,
     struct genl_info *info, void *arg)
{
 int ret;

 switch (cmd->c_id) {

 case THERMAL_GENL_CMD_TZ_GET_ID:
  ret = parse_tz_get(info, arg);
  break;

 case THERMAL_GENL_CMD_CDEV_GET:
  ret = parse_cdev_get(info, arg);
  break;

 case THERMAL_GENL_CMD_TZ_GET_TEMP:
  ret = parse_tz_get_temp(info, arg);
  break;

 case THERMAL_GENL_CMD_TZ_GET_TRIP:
  ret = parse_tz_get_trip(info, arg);
  break;

 case THERMAL_GENL_CMD_TZ_GET_GOV:
  ret = parse_tz_get_gov(info, arg);
  break;

 case THERMAL_GENL_CMD_THRESHOLD_GET:
  ret = parse_threshold_get(info, arg);
  break;

 default:
  return THERMAL_ERROR;
 }

 return ret;
}

static struct genl_cmd thermal_cmds[] = {
 {
  .c_id  = THERMAL_GENL_CMD_TZ_GET_ID,
  .c_name  = (char *)"List thermal zones",
  .c_msg_parser = handle_netlink,
  .c_maxattr = THERMAL_GENL_ATTR_MAX,
  .c_attr_policy = thermal_genl_policy,
 },
 {
  .c_id  = THERMAL_GENL_CMD_TZ_GET_GOV,
  .c_name  = (char *)"Get governor",
  .c_msg_parser = handle_netlink,
  .c_maxattr = THERMAL_GENL_ATTR_MAX,
  .c_attr_policy = thermal_genl_policy,
 },
 {
  .c_id  = THERMAL_GENL_CMD_TZ_GET_TEMP,
  .c_name  = (char *)"Get thermal zone temperature",
  .c_msg_parser = handle_netlink,
  .c_maxattr = THERMAL_GENL_ATTR_MAX,
  .c_attr_policy = thermal_genl_policy,
 },
 {
  .c_id  = THERMAL_GENL_CMD_TZ_GET_TRIP,
  .c_name  = (char *)"Get thermal zone trip points",
  .c_msg_parser = handle_netlink,
  .c_maxattr = THERMAL_GENL_ATTR_MAX,
  .c_attr_policy = thermal_genl_policy,
 },
 {
  .c_id  = THERMAL_GENL_CMD_CDEV_GET,
  .c_name  = (char *)"Get cooling devices",
  .c_msg_parser = handle_netlink,
  .c_maxattr = THERMAL_GENL_ATTR_MAX,
  .c_attr_policy = thermal_genl_policy,
 },
        {
                .c_id           = THERMAL_GENL_CMD_THRESHOLD_GET,
                .c_name         = (char *)"Get thresholds list",
                .c_msg_parser   = handle_netlink,
                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
                .c_attr_policy  = thermal_genl_policy,
        },
        {
                .c_id           = THERMAL_GENL_CMD_THRESHOLD_ADD,
                .c_name         = (char *)"Add a threshold",
                .c_msg_parser   = handle_netlink,
                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
                .c_attr_policy  = thermal_genl_policy,
        },
        {
                .c_id           = THERMAL_GENL_CMD_THRESHOLD_DELETE,
                .c_name         = (char *)"Delete a threshold",
                .c_msg_parser   = handle_netlink,
                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
                .c_attr_policy  = thermal_genl_policy,
        },
        {
                .c_id           = THERMAL_GENL_CMD_THRESHOLD_FLUSH,
                .c_name         = (char *)"Flush the thresholds",
                .c_msg_parser   = handle_netlink,
                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
                .c_attr_policy  = thermal_genl_policy,
        },
};

static struct genl_ops thermal_cmd_ops = {
 .o_name  = (char *)"thermal",
 .o_cmds  = thermal_cmds,
 .o_ncmds = ARRAY_SIZE(thermal_cmds),
};

struct cmd_param {
 int tz_id;
 int temp;
 int direction;
};

typedef int (*cmd_cb_t)(struct nl_msg *, struct cmd_param *);

static int thermal_genl_tz_id_encode(struct nl_msg *msg, struct cmd_param *p)
{
 if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id))
  return -1;

 return 0;
}

static int thermal_genl_threshold_encode(struct nl_msg *msg, struct cmd_param *p)
{
 if (thermal_genl_tz_id_encode(msg, p))
  return -1;

 if (nla_put_u32(msg, THERMAL_GENL_ATTR_THRESHOLD_TEMP, p->temp))
  return -1;

 if (nla_put_u32(msg, THERMAL_GENL_ATTR_THRESHOLD_DIRECTION, p->direction))
  return -1;

 return 0;
}

static thermal_error_t thermal_genl_auto(struct thermal_handler *th, cmd_cb_t cmd_cb,
      struct cmd_param *param,
      int cmd, int flags, void *arg)
{
 thermal_error_t ret = THERMAL_ERROR;
 struct nl_msg *msg;
 void *hdr;

 msg = nlmsg_alloc();
 if (!msg)
  return THERMAL_ERROR;

 hdr = genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, thermal_cmd_ops.o_id,
     0, flags, cmd, THERMAL_GENL_VERSION);
 if (!hdr)
  goto out;

 if (cmd_cb && cmd_cb(msg, param))
  goto out;

 if (nl_send_msg(th->sk_cmd, th->cb_cmd, msg, genl_handle_msg, arg))
  goto out;

 ret = THERMAL_SUCCESS;
out:
 nlmsg_free(msg);

 return ret;
}

thermal_error_t thermal_cmd_get_tz(struct thermal_handler *th, struct thermal_zone **tz)
{
 return thermal_genl_auto(th, NULL, NULL, THERMAL_GENL_CMD_TZ_GET_ID,
     NLM_F_DUMP | NLM_F_ACK, tz);
}

thermal_error_t thermal_cmd_get_cdev(struct thermal_handler *th, struct thermal_cdev **tc)
{
 return thermal_genl_auto(th, NULL, NULL, THERMAL_GENL_CMD_CDEV_GET,
     NLM_F_DUMP | NLM_F_ACK, tc);
}

thermal_error_t thermal_cmd_get_trip(struct thermal_handler *th, struct thermal_zone *tz)
{
 struct cmd_param p = { .tz_id = tz->id };

 return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
     THERMAL_GENL_CMD_TZ_GET_TRIP, 0, tz);
}

thermal_error_t thermal_cmd_get_governor(struct thermal_handler *th, struct thermal_zone *tz)
{
 struct cmd_param p = { .tz_id = tz->id };

 return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
     THERMAL_GENL_CMD_TZ_GET_GOV, 0, tz);
}

thermal_error_t thermal_cmd_get_temp(struct thermal_handler *th, struct thermal_zone *tz)
{
 struct cmd_param p = { .tz_id = tz->id };

 return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
     THERMAL_GENL_CMD_TZ_GET_TEMP, 0, tz);
}

thermal_error_t thermal_cmd_threshold_get(struct thermal_handler *th,
                                          struct thermal_zone *tz)
{
 struct cmd_param p = { .tz_id = tz->id };

        return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
     THERMAL_GENL_CMD_THRESHOLD_GET, 0, tz);
}

thermal_error_t thermal_cmd_threshold_add(struct thermal_handler *th,
                                          struct thermal_zone *tz,
                                          int temperature,
                                          int direction)
{
 struct cmd_param p = { .tz_id = tz->id, .temp = temperature, .direction = direction };

        return thermal_genl_auto(th, thermal_genl_threshold_encode, &p,
     THERMAL_GENL_CMD_THRESHOLD_ADD, 0, tz);
}

thermal_error_t thermal_cmd_threshold_delete(struct thermal_handler *th,
                                             struct thermal_zone *tz,
                                             int temperature,
                                             int direction)
{
 struct cmd_param p = { .tz_id = tz->id, .temp = temperature, .direction = direction };

        return thermal_genl_auto(th, thermal_genl_threshold_encode, &p,
     THERMAL_GENL_CMD_THRESHOLD_DELETE, 0, tz);
}

thermal_error_t thermal_cmd_threshold_flush(struct thermal_handler *th,
                                            struct thermal_zone *tz)
{
 struct cmd_param p = { .tz_id = tz->id };

        return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
     THERMAL_GENL_CMD_THRESHOLD_FLUSH, 0, tz);
}

thermal_error_t thermal_cmd_exit(struct thermal_handler *th)
{
 if (genl_unregister_family(&thermal_cmd_ops))
  return THERMAL_ERROR;

 nl_thermal_disconnect(th->sk_cmd, th->cb_cmd);

 return THERMAL_SUCCESS;
}

thermal_error_t thermal_cmd_init(struct thermal_handler *th)
{
 int ret;
 int family;

 if (nl_thermal_connect(&th->sk_cmd, &th->cb_cmd))
  return THERMAL_ERROR;

 ret = genl_register_family(&thermal_cmd_ops);
 if (ret)
  return THERMAL_ERROR;

 ret = genl_ops_resolve(th->sk_cmd, &thermal_cmd_ops);
 if (ret)
  return THERMAL_ERROR;

 family = genl_ctrl_resolve(th->sk_cmd, "nlctrl");
 if (family != GENL_ID_CTRL)
  return THERMAL_ERROR;

 return THERMAL_SUCCESS;
}